I'm proposing this series for v6.2 (for-next).

For quite some time, we've been encouraged to disable filecache
garbage collection for NFSv4 files, and I think I found a surgical
way to do just that. That is presented in "NFSD: Add an NFSD_FILE_GC
flag to enable nfsd_file garbage collection".

The other major change in this set is reworking the file_hashtbl to
resize itself dynamically. This reduces the average size of its
bucket chains, greatly speeding up hash insertion, which holds the
state_lock.

The current rhashtable changes are failing some tests, so expect
another revision of this series soon.

Comments and opinions are welcome.

Changes since v4:
- Addressed some comments in the GC patch; more to come
- Split clean-ups out of the rhashtable patch, reordered the series
- Removed state_lock from the rhashtable helpers

Changes since v3:
- the new filehandle alias check was still not right

Changes since v2:
- Converted nfs4_file_rhashtbl to nfs4_file_rhltable
- Addressed most or all other review comments


Changes since RFC:
- checking nfs4_files for inode aliases is now done only on hash
insertion
- the nfs4_file reference count is now bumped only while the RCU
read lock is held
- comments and function names have been revised and clarified

---

Chuck Lever (13):
      NFSD: Pass the target nfsd_file to nfsd_commit()
      NFSD: Revert "NFSD: NFSv4 CLOSE should release an nfsd_file immediately"
      NFSD: Add an NFSD_FILE_GC flag to enable nfsd_file garbage collection
      NFSD: Clean up nfs4_preprocess_stateid_op() call sites
      NFSD: Trace delegation revocations
      NFSD: Use const pointers as parameters to fh_ helpers
      NFSD: Update file_hashtbl() helpers
      NFSD: Clean up nfsd4_init_file()
      NFSD: Add a remove_nfs4_file() helper
      NFSD: Clean up find_or_add_file()
      NFSD: Refactor find_file()
      NFSD: Allocate an rhashtable for nfs4_file objects
      NFSD: Use rhashtable for managing nfs4_file objects


 fs/nfsd/filecache.c |  81 +++++++++++++++--------
 fs/nfsd/filecache.h |   4 +-
 fs/nfsd/nfs3proc.c  |  10 ++-
 fs/nfsd/nfs4proc.c  |  42 +++++-------
 fs/nfsd/nfs4state.c | 157 +++++++++++++++++++++++---------------------
 fs/nfsd/nfsfh.h     |  10 +--
 fs/nfsd/state.h     |   5 +-
 fs/nfsd/trace.h     |  58 +++++++++++++++-
 fs/nfsd/vfs.c       |  19 ++----
 fs/nfsd/vfs.h       |   3 +-
 10 files changed, 239 insertions(+), 150 deletions(-)

--
Chuck Lever